Free-standing tank assembly with structural framing

ABSTRACT

This invention corresponds to a freestanding tank assembly with structural framing ( 1 ) that contains: 
     One self-supporting cylindrical tank ( 2 ) of vertical storage of fluids, whose relation face Height/Diameter (H/D) is between 2.5 and 3.5, and has a volumetric capacity between 68.14 m 3  (18000 liquid gals) and 75.71 m 3  (20000 liquid gals). 
     One structural framing ( 3 ) formed by a longitudinal portion ( 3   a ) and one base portion ( 3   b ), assembled together forming “L”, being such longitudinal portion ( 3   a ) joined to self-supporting cylindrical tank ( 2 ) through solid mounts ( 3   c ), being such base portion ( 3   b ) joined to flat base ( 2   c ) of self-supporting cylindrical tank ( 2 ) in such way that such base portion ( 3   b ) of quadrilateral main surface surrounding the flat base ( 2   c ) circular of self-supporting cylindrical tank ( 2 ).

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to vertical tanks for the storage of fluids and, more particularly, to those tanks that are readily transported and self-supporting.

2. Description of the Related Art

Several designs for storage tanks have been designed in the past. None of them, however, include the characteristics of the present invention.

The storage of fluids, such as petroleum and petrochemical products, requires tanks with high volumetric capacity, that are typically designed with reduced height and large diameters. The need to have tanks with these dimensions creates various design, transportation and installation challenges. These robust tanks are not manufactured in a factory, they need to be built on site at the plants or operation fields. This practice causes high costs.

The transportation of these large tanks is another problem. Their transportation is not authorized in many, if not most, highways. Special permits and precautions are needed. Additionally, the topography and other characteristics of the roads increase the danger in their transportation.

With respect to the installation of large storage tanks, it is necessary to have large areas available and preliminary preparations for very good foundations that allow the equipment to be anchoraged and guarantee their stability in plants or fields to withstand the elements such as seismic phenomena, strong winds, etc. All these factors increase the installation costs.

There are numerous storage tanks in the market with different dimensions and specifications. It is common to identify tanks with huge dimensions that can be transported in some International highways such as those of North America, but require strong foundations for their installation and require a large footprint.

Also there are vertical tanks for storage of fluids that require less supporting area but are constructed with a reduced volumetric capacity. Unfortunately, this condition is not practical for the requirements of industries like the petroleum and petrochemical industries requiring large storage capacity.

Taking in consideration the above mentioned needs and limitation, it is still necessary to develop a tank with high storage capacity, transportable, easy to install, stable that withstands natural phenomenon that contributes to reduction of available plant area, manufacturing, installation and operation costs.

Other documents describing the closest subject matter provide for a number of more or less complicated features that fail to solve the problem in an efficient and economical way. None of these patents suggest the novel features of the present invention.

SUMMARY OF THE INVENTION

It is one of the objects of the present invention to provide a tank with high storage capacity, transportable, easy to install, stable that withstands natural phenomenon that contributes to reduction of available plant area, manufacturing, installation and operation costs.

It is another object of this invention to provide a a robust vertical tank for storage of fluids, transportable throughout roads with different characteristics occupying less surface area, that does not require conventional foundations and that guarantee stability while withstanding wind and seismic phenomena.

BRIEF DESCRIPTION OF THE DRAWINGS

With the above and other related objects in view, the invention consists in the details of construction and combination of parts as will be more fully understood from the following description, when read in conjunction with the accompanying drawings in which:

FIG. 1 is an isometric view of a self-supporting tank with structural framing (1) where is displayed the self-supporting cylindrical tank (2) and structural framing (3).

FIG. 2 is a front elevational view of self-supported cylindrical tank (2) showing conical roof (2 a), housing (2 b), flat base (2 c) and “manhole” (2 d).

FIG. 3 is a right side elevational view of self-supporting cylindrical tank (2) showing flanges (2 e), way in “L” of structural framing (3), stairs (3 d) life line (3 e).

FIG. 4 is a left side elevational view of self-supporting cylindrical tank (2) showing structural framing (3) formed by longitudinal portion (3 a) and base portion (3 b) as well as solid mounts (3 c).

FIG. 5 is a rear elevational view of self-supporting cylindrical tank (2) showing stringers (3 ax, 3 ay), sections (3 ax) and external cylindrical sections (3 ax′) that form longitudinal portion (3 a) of structural framing (3).

FIG. 6 is a top view of self-supporting cylindrical tank (2) showing its disposition of portions (3 a, 3 b, 3 c) of structural framing (3), vent nozzles (2 an), flange (2 am), the last ones included in conical roof (2 a).

FIG. 6a shows a specific detail of solid mount parts (3 c) joining housing (2 b) of self-supporting cylindrical tank (2) with longitudinal portion (3 a) of structural framing (3).

FIG. 7 shows a bottom view of self-supporting cylindrical tank (2) showing main area of base portion (3 b) and reticule formed by sections (3 bx, 3 bx′, 3 by, 3 by′).

FIG. 8 presents view in perspective of portions (3 a, 3 b) of structural framing (3) together with each one of parts that form it.

FIG. 9 is an isometric view showing details of structural framing (3) with solid mounts (3 c) mounted thereto.

BRIEF DESCRIPTION OF INVENTION

Below is described one of modalities of invention without limitation to its scope.

This utility model corresponds to Freestanding Tank Assembly with Structural Framing (1) that contains:

A self-supporting cylindrical tank (2) of vertical storage of fluids, whose relation Face Height/Diameter (H/D) is between 2.5 and 3.5, and has a volumetric capacity between 68.14 m³ (18000 liquid gals) and 75.71 m³ (20000 liquid gals).

An structural framing (3) formed by a longitudinal portion (3 a) and a base portion (3 b), such portions assembled together forming “L”, being such longitudinal portion (3 a) joined to self-supporting cylindrical tank (2) through solid mounts (3 c), being such base portion (3 b) joined to flat base (2 c) of self-supporting cylindrical tank (2) in such way that such base portion (3 b) of quadrilateral main surface, surrounding flat base (2 c) circular of self-supporting cylindrical tank (2).

DETAILED DESCRIPTION OF THE EMBODIMENTS OF THE INVENTION

Following is description of one of modalities of invention which is not limitation to scope of invention defined in claims.

Settings

According to FIG. 1, this invention that corresponds to Freestanding Tank Assembly with Structural Framing (1) is formed, in general terms, by two main components: one self-supporting cylindrical tank (2) of vertical storage of fluids and one structural framing (3). The expression “self-supporting” makes reference to quality of vertical tank to sustain itself without need any anchorage to floor of industrial plant. This means that the vertical tank can be installed and put in operation without requiring construction of strong foundations with high cost or using external attachments such as cables or turnbuckles to contribute to its stability, considering that such tank has a volumetric capacity between 68.14 and 75.71 m³ (18000 to 20000 liquid gals).

The self-supporting cylindrical tank (2) of vertical storage of fluids has a ratio Face Height/Diameter (H/D) between 2.5 and 3.5. In one of the embodiments of the invention, tank (2) can have a diameter between 2.74 and 3.2 m (between 9 and 10.5 feet) and a front height between 7.62 and 9.45 m (between 25 and 31 feet).

The self-supporting cylindrical tank (2) is an equipment designed for storage of industrial liquids fluids, specially those considered in petrochemical and petroleum industries, but it is not limited to them. The tank is manufactured using steel sheets, particularly, carbon steel, according to international standards.

In FIG. 2 it can be seen that self-supporting cylindrical tank (2) is a vertical tank including a conical roof (2 a), a housing (2 b) of cylindrical way and a flat base (2 c). The conical roof (2 a) has vent nozzles (2 an) and flange (2 am), this last one for connection of gases discharges tubes for its further processing according to requirements of each industrial process (see FIG. 6).

Housing (2 d) includes a metallic sheet with right cylindrical way whose thickness is calculated according to height values of fluid column to be stored and its hydrostatic pressure. Housing (2 b) has in the closest portion to flat base (2 c), “manhole” (2 d) and flanges (2 e) for its connection with tubes and other accessories required in operation. The dimensions of flanges (2 e) can be calculated by a person trained in this field and it must be adequate for fast filling, which normally can reach a flow rate 1.15 m³/min.

The self-supporting cylindrical tank (2) which is part of this invention is a vertical tank; this means that it must be operated in vertical way because its specific design makes impossible its operation as horizontal cylindrical tank. Its relation Face Height/Diameter (H/D) is between 2.5 and 3.5, and it has volumetric capacity between 68.14 m³ (18000 liquid gals) and 75.71 m³ (20000 liquid gals).

On the other hand, this invention also incorporates a structural framing (3) attached to vertical cylindrical tank that guarantees structural stability of tank during its transportation and its stability facing up critical seismic phenomena and presence of strong winds, disregarding of robust and expensive foundations construction for rest and permanent anchorage of equipment.

In FIG. 3 can be noted that structural framing (3) of this utility model consist in metal framework constructed with steel profiles formed by two portions: one longitudinal portion (3 a) and one base portion (3 b). Such portions are assembled perpendicularly forming together Framework in “L” way.

Longitudinal portion (3 a) together with solid mounts (3 c) facilitate horizontal transportation of equipment and avoid its deformation during displacing by highway. Meanwhile, base portion (3 b) is used as support platform for vertical tank when it is installed and protects flat base (2 c) of vertical cylindrical tank avoiding deformations or failures due to hydrostatic pressure of fluids column stored.

Structural framing (3) in its all whole allow guarantee tank stability facing up critical seismic conditions and wind. If each portion of framing fulfills a particular function, all portions surpass total problems presented.

In FIG. 4 is possible see disposition of solid mounts (3 c) that join external structure (3) to self-supporting cylindrical tank (2).

The expression “solid mounts” indicates that such supports are solid elements without holes. These solid mounts (3 c) are put in parallel way each other and throughout of cylindrical tank.

In FIG. 5 can be noted longitudinal portion (3 a) that is formed by sections (3 ax) of equal size, parallel and spaced, joined in its ends to pair of longitudinal crossbars (3 ay) in angle of 90°, in such way that such longitudinal crossbars are parallel each other.

Longitudinal portion (3 a) has pair of external cylindrical sections (3 ax′), where one of them is placed in summit zone of longitudinal portion (3 a) and the other one is placed in vertex area of structural framing (3).

It is understood as “summit zone” the highest area of longitudinal portion (3 a) when apparatus is put in plant and it is understood as “vertex area”, the nearest zone to geometrical vertex of structural framing (3), this means, closer zone where the longitudinal portion (3 a) is joined to base portion (3 b).

Configuration of structural framing (3) is suitable for tank can be transported in horizontal way and together with solid mounts (3 c) guarantee dimensional stability of apparatus without risk of failures or deformations due to vibration presented during displacing.

In FIGS. 6 and 7 that present a superior and inferior view of invention, can be noted the base portion (3 b) which is formed by a quadrilateral structure, specially square, constructed with four perimeter crossbars (3 bx, 3 by), structure that houses in its interior square space a reticule formed by a plurality of sections (3 b, 3 byx′, 3 by′) crossed and joined each other to form quadrilateral spaces in net way.

In one of the modalities of the invention, the reticule is formed by twenty sections (3 by′) and four sections (3 by′) as in FIG. 8 or 9.

The base portion (3 b) of structural framing (3) is joined to flat base (2 c) of self-supporting cylindrical tank (2) in such way that such base portion (3 b) surrounding flat base (2 c) circular of mentioned tank. In geometrical terms, the quadrilateral of base portion (3 b) contains or has inside flat base (2 c) circular of tank. This characteristic is very important in order to guarantee stability facing up seismic and wind taking in consideration the high volumetric capacity and ratio Face Height/Diameter that the cylindrical tank of this utility model has.

In FIG. 8 is possible see configuration of structural framing (3) in form of “L”. Parts of structural framing (3), as well as sections (3 ax), longitudinal crossbars (3 ay), perimeter crossbars (3 bx, 3 by) and sections (3 bx′, 3 by′) are double T angular metallic profiles, preferably in steel, which are joined through welding. Welding details are known amply by persons regularly trained in this matter.

External cylindrical sections (3 ax′) are of circular transversal section and are made in steel, being joined to longitudinal crossbars (3 ay) through welding.

The self-supporting cylindrical tank (2) is joined to longitudinal portion (3 a) of structural framing (3) through multiple solid mounts (3 c) that are solid metallic supports preferably in steel that have cradle shape, formed by curve flange (3 ca) coincident with external flange of self-supporting cylindrical tank (2), stiffeners of multiple sections (3 cd), flat plaques (3 cb) and one base plaque (3 ce), as can be noted in FIGS. 6 and 6 a.

Base plaque (3 ce) of each one of solid mounts (3 c) is joined to each one of sections (3 ax) of longitudinal portion (3 a) of structural framing (3) as can be saw in FIG. 9 and in turn, each one of curve flanges (3 ca) of solid mounts (3 c) are joined to housing (2 b) of vertical cylindrical tank.

The sheets with which is designed the tank correspond to steel sheets, preferably carbon steel whose thickness can be among 4 and 7 mm for housing (2 b), and between 8 and 10 mm for base portion (2 c).

All profiles used in construction of structural framing (3) correspond to standard metal profiles of commercial sale, as well as the accessories such as flanges and nozzles.

This invention can have other accessories knew for any person regularly trained in the matter, such as anti-fire systems immersed with injection of anti-fire liquids, ascent and descent stairs, life lines, device of cathode protection, purge, devices of level, pressure and temperature control, among others, fully known by people trained in the matter.

Technical Effects and Advantages

This invention presents technical advantages such as:

Freestanding Tank Assembly with Structural Framing does not require to be constructed in plants in which it will be used;

It has maximum volume in tanks that can be transported by the Colombian highways;

It is fully transportable without risk of deformations throughout Colombian roads and it meets guidelines from Transit National Code;

Because it does not require anchorage to floor for its operation, the need to construct complex and expensive foundations for its installation is deleted;

Vertical storage of this freestanding tank assembly with structural framing savings considerable space in comparison with horizontal storage of same volume. The saving is of 40% of plant surface, which involves additional saving in tubes and other accessories to connection, saving in civil work of adequacy and in installation term;

Although it does not require anchorage to floor, it guarantees complete stability facing up seismic phenomenon and extreme condition of wind.

This invention was subjected to studies of high level through simulation by analysis of finite elements with which could be confirmed that its performance is those that the inventor expected.

Studies regarding to seismic and wind phenomenon covered verification of invention performance facing up possible critical conditions:

In situations of seismic peak according to Anti-Seismic Norms, being filled of fluid to its maximum storage capacity.

In situations of strong wind according to Colombian Wind and Wind Energy Atlas, being the invention completely empty.

Results get were satisfactory passing various tests.

Also, tests were made during tank hoisting, tank suspended in air, discharge of tank and placing in plant.

Other installation and put in operation considerations are conventional and are knew by people regularly trained in this matter.

Due to above mentioned characteristics and advantages, this invention constitutes the largest equipment of vertical storage transportable by roads such as the Colombia roads, that does not require any anchorage to floor, occupying small space within petroleum plants or fields, having satisfactory stability facing up possible seismic phenomenon and strong wind. 

What is claimed is:
 1. A freestanding tank assembly with structural framing (1), comprising: a self-supporting cylindrical tank (2) of vertical storage of fluids, whose ratio face height/diameter (H/D) is between 2.5 and 3.5, and has volumetric capacity between 68.14 m³ (18000 liquid gals) and 75.71 m³ (20000 liquids gals); and a structural framing (3) formed by a longitudinal portion (3 a) and a base portion (3 b), assembled such portions together forming “L”, being such longitudinal portion (3 a) joined to self-supporting cylindrical tank (2) through solid mounts (3 c), being such base portion (3 b) joined to flat portion (2 c) of self-supporting cylindrical tank (2) in such way that the base portion (3 b) of quadrilateral main surface surrounding circular flat base (2 c) of self-supporting cylindrical tank (2).
 2. A freestanding tank assembly with structural framing (1) as set forth in claim 1, where self-cylindrical tank (2) is a vertical tank including a conical roof (2 a), a housing (2 b) of cylindrical shape and a flat base (2 c).
 3. A freestanding Tank Assembly with Structural Frame (1) as set forth in claim 2, where conical roof (2 a) has vent nozzles (2 an) and flange (2 am).
 4. A freestanding tank assembly with structural frame (1) as set forth in claim 2, where housing (2 b) has a cylindrical shape having a manhole (2 d) and flanges (2 e).
 5. A freestanding tank assembly with structural framing (1) as set forth in claim 1, where structural framing (3) has a longitudinal portion (3 a) formed by sections (3 ax) of same size, parallel and spaced, joined in their ends to pair of longitudinal crossbars (3 ay) in angle of 90°, in such way that longitudinal crossbars (3 ay) also are parallel together.
 6. A freestanding tank assembly with structural framing (1) as set forth in claim 5, where longitudinal portion (3 a) has pair of external cylindrical sections (3 ax′), one placed in summit zone of longitudinal portion (3 a) and other one placed in vertex area of structural framing (3).
 7. A freestanding tank assembly with structural framing (1) as set forth in claim 5, where sections (3 ax), longitudinal crossbars (3 ay), perimeter crossbars (3 bx, 3 by) and sections (3 bx′,3 by′) are double T angular metal profiles.
 8. A freestanding tank assembly with structural framing (1) as set forth in claim 1, where structural framing (3) has a base portion (3 b) formed by a Squire structure constructed with four perimeter crossbars (3 bx, 3 by), structure that houses in its interior square space a reticule formed by plurality of sections (3 bx′, 3 by′) crossed and joined each other in order to form quadrilateral spaces in net way.
 9. A freestanding tank assembly with structural framing (1) as set forth in claim 1, where solid mounts (3 c) are solid metallic supports with cradle shape, formed by curve flange (3 ca) coincident with housing curve (2 b) of self-supporting cylindrical tank (2), stiffeners of many sections (3 cd), flat plaques (3 cb) and one base plaque (3 ce).
 10. A freestanding tank assembly with structural framing (1) as set forth in claim 9, in which each curve flange (3 ca) of each solid mount (3 c) is joined to housing (2 b) and each base plaque (3 ce) of each solid mount (3 c) is joined to each section (3 ax) of longitudinal portion (3 a). 